Strategic capacity allocation in hybrid solar-wind-hydro-storage systems considering power operational dispatch: A bilevel Nash game

Hybrid solar-wind-hydro-storage systems leverage complementary advantages to mitigate renewable intermittency, yet face critical challenges in multi-stakeholder capacity allocation and grid integration costs. A non-cooperative set of three players, including hydro, photovoltaic, and wind turbine power plants, is constructed, in which battery is integrated to satisfy their respective dispatches. A bilevel Nash game framework is proposed for strategic capacity allocation in a hybrid three-player to minimize the comprehensive investment and operation costs, addressing competitive dynamics among independent stakeholders. The model decouples decision-making into hierarchical layers: upper-level capacity bidding solved through genetic algorithm, and lower-level market-driven dispatch optimized via mixed-integer linear programming. The novelty of this framework lies in the integration of a non-cooperative game structure within a bilevel optimization to resolve the strategic competition-operation coupling in multi-owner systems. Renewable and demand uncertainties in hybrid systems are incorporated using Latin Hypercube Sampling and scenario reduction techniques. Applied to a 2200 MW hydropower plant in Tibet, the optimized configuration to satisfy the maximum electric demand of 5717 MW allocates 10,062 MW solar PV with 20,344 MWh battery storage and 946 MW wind power with 5465 MWh storage. The simulation results demonstrate that the strategic storage deployment reduces grid dependence by 42 % via price arbitrage, while economic asymmetries shape distinct roles: PV as baseload (49.4 % supply), wind as peaker with penalty risks, and hydro as flexible regulator (24.5 % supply). The equilibrium solution demonstrates that no player can unilaterally improve costs, validating the framework's efficacy in balancing investor competition with operational feasibility.